Assessment of NOAA-21 OMPS Nadir Mapper SDR Reflectance Using Deep Convective Clouds As Calibration Targets

The Ozone Mapping and Profiler Suite (OMPS) Nadir Mapper (NM) sensor is one of the two nadir sensors for OMPS. OMPS instruments are flying onboard the Suomi National Polar-orbiting Partnership (S-NPP) satellite [1], National Oceanic and Atmospheric Administration-20 (NOAA-20) and NOAA-21 satellites. The lifetime performance of the OMPS-NM Sensor Data Record (SDR) data is critical for the user community since the data are widely used for ozone profile retrievals, total ozone retrievals and climate studies [2]. OMPS-NM on board NOAA-21 satellite is the newest of its kind. A series of calibration efforts have been performed by OMPS SDR team at NOAA since it was launched on November 10, 2022, The OMPS SDR for NOAA-21 has reached Provisional Maturity level in April 2023 [3,4].

In this study, NOAA-21 OMPS-NM SDR data stability is assessed through Earth view reflectance within Deep Convective Cloud (DCC) calibration targets. DCCs are the brightest tropical Earth targets located in a thin band near the equator called Inter-Tropical Convergence Zone (ITCZ) [5]. They are ideal visible calibration targets with nearly a Lambertian reflectance [6,7]. OMPS-NM pixels over DCCs can be identified using infrared threshold from collocated VIIRS brightness temperature measurements at 11-µm band. Preliminary analysis shows that reprocessed and operational S-NPP OMPS-NM SDR data long-term reflectance is stable within 1% changes per ten years using DCCs as calibration targets [8,9]. In this study, this method will be further applied to the NOAA-21 OMPS-NM reflectance to investigate the stability of NOAA-21 OMPS-NM reflectance over the DCC regions. In addition, this study will assess inter-sensor radiometric calibration biases between the NOAA-21 and SNPP NM data over the DCC regions.

Disclaimer: the presentation contents are solely the opinions of the authors and do not constitute a statement of policy, decision, or position on behalf of NOAA or the U. S. Government.

References

[1] Pan, Chunhui, et al. (2013): Performance and Calibration of the Nadir Suomi-NPP Ozone mapping Profiler Suite From Early-Orbit Images. IEEE Journal of Selected Topics in Applied Earth Observation and Remote Sensing, vol. 6, No. 3, 1539-1551

[2] Flynn, L., et al. (2014), Performance of the ozone mapping and profiler suite (OMPS) products, J. Geophys. Res. Atmos., doi:10.1002/2013JD020467.

[3] Yan B., T. Beck, J. Chen and other co-authors: NOAA-21 OMPS NM and NP SDR report for beta maturity review, NOAA JPSS Science Review, February 2023, //www.star.nesdis.noaa.gov/jpss/documents/AMM/N21/NOAA-21_OMPS_Beta.pdf.

[4] Yan B., T. Beck, J. Chen and other co-authors: NOAA-21 OMPS NM and NP SDR report for provisional maturity review, NOAA JPSS Science Review, April 2023, //www.star.nesdis.noaa.gov/jpss/documents/AMM/N21/NOAA-21_OMPS_Provisional.pdf.

[5] Doelling, D, and et al., “Vicarious Calibration and Validation,” In Comprehensive Remote Sensing; Liang, S., Ed.; Elsevier: Oxford, UK, 2018; Volume 1, pp. 475–518.

[6] Doelling, D. and et al., “The Characterization of Deep Convective Clouds as an Invariant Calibration Target and as a Visible Calibration Technique,” Geoscience and Remote Sensing, IEEE Transactions on, 51(3), 1147-1159 (2013).

[7] Wenhui Wang, Changyong Cao, "Assessing the VIIRS RSB calibration stability using deep convective clouds," Proc. SPIE 9264, Earth Observing Missions and Sensors: Development, Implementation, and Characterization III, 926410 (19 November 2014); doi: 10.1117/12.2068434

[8] Yan, B, and et al., W. New Reprocessing towards Life-Time Quality-Consistent Suomi NPP OMPS Nadir Sensor Data Records (SDR): Calibration Improvements and Impact Assessments on Long-Term Quality Stability of OMPS SDR Data Sets. Remote Sens. 2022, 14, 3125. https://doi.org/10.3390/rs14133125.

[9] D. Liang, B. Yan, L. Flynn, T. Beck, N. Sun, and J. Huang, ‘Long-Term Stability Assessment of Reprocessed S-NPP OMPS-NM SDR Data Sets Using Deep Convective Cloud Targets: Feasibility Study’, IGARSS 2023, Pasadena, California, 16 July to 21 July, 2023.